Since the feh channel where they introduced heroic grails everyone has been teorycrafting their favorite or desired unit at +10.
I recommend everyone to not spend grails immediately for 1 or 2 copy of the unit untill you have enougth to +10 said unit as getting 1 or 2 merges usually don't affect too much the unit while you may need some other unit for fodder or they may introduce a new GHB or TT that you may like more before you finish max merging that unit.
Waiting is better than regretting
I can certainly get behind saving them up.
A lot of TT and GHB heroes are up for a refine, and we might get newer, better ones (The 20 nov banner has a GHB to go with it)
So the 'best choice' will likely shift.
Just look at what happened to Alm and Saber, they went from near useless to two of the best sword units with their refine.
To each their own - I'm personally stockpiling my grails as I'm not tempted to try and make a +10 GHB unit. Still working on my first +10 regular unit... if only the dang game would quit giving me Effie's and let me pull 2 more Catria.
I am glad for the Grails though as I foddered Brazen Def/Res to Catria, and now I don't have to feel bad for sacrificing a limited unit for it, since I have replaced it.
When they do add Aversa I may be tempted to pick up a copy or 2 of her after merging my other copies together.
Completely agree. But first, I need 50 more grails and Masked Marth will be my FIRST 5*+10 unit.
Day 1 player. First year didn't really prioritize any merge projects, except MM since she was a waste of barrack space having no fodder, and didn't want to send her home. So she is now +9, and waiting on 50 grails for that second copy to be +10. Getting close to 20k feathers for this to be finally happening.
Next will be saving the grails until there's a more definite unit to invest in.
Another thing to consider before rushing merges, we may get another copy of that specific unit so you may use your grails then have an additional copy for no reason. This may only be relevant to the ones that we have gotten tons of copies of. The newer ones will be years til you can get +10 for "free".
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